Apparatus for evaporating or concentrating liquids.



E. SHAW. APPARATUS FOR EVAPORATING 0R CONCENTRATING LIQUIDS. APPLICATIONFILED DBO. 2a, 1909.

4 SHEETS-SHEET 1.

Patented July 26, 1910.

E. SHAW. APPARATUS FOR EVAPORATING 0R GONG'ENTRATING LIQUIDS.

APPLICATION FILED DEC. 23, 1909.

Patented July 26, 1910.

E. SHAW. APPARATUS FOR EVAPORATING OR GONGBNTRATING LIQUIDS. APPLIOATIONFILED DEC. 28, 1909.

%m%% Patented July 26, 1910.

4 SHEETS-SHEET 3.

E. SHAW. APPARATUS FOR EVAPORATING 0R GONGENTEATING LIQUIDS.

APPLICATION FILED D150. 28, 1909.

Patented July 26, 1910.

" 4 sums-sum 4.

a l F UNITED STATES PATENT OFFI E? EDWARD SHAW, OF DARTFQRD HEATH,ENGLAND.

A APPARATUS ron. EvAronA'rINeoncoNcENrnA'rme mourns.

Specification of Letters Patent. Patel lined J uly 26, 1910.

application filed December 28, 1909. Serial No. 535,320.

To all whom it may concern: Be it known that I, EnwARnSnAw, a subject ofthe King of Great Britain and Ireland, residing at Dartford Heath, inthe county of Kent, England, have invented Improvements in Apparatus'forEvaporating or Concentrating Liquids, of which the fol lowing, is aspecification.

This invention has reference to apparatus for evaporating orconcentrating liquids generally, for example cane juice, sugarsolutions, alkaline solutions, etc., and for the treatment of syrups inthe manufacture of In such machines it has been heretofore proposed toforce the liquid through the heated tube b means of an adj us'table pumpwhich provi es a positive control of the rate of flow of the liquid.Moreover, for

the purpose of providing in an externally heated evaporating tube apassage way 1ncreasing in area toward the exit end according to theincreasing volume of vapor, it has been proposed to constitute suc a'tubeof a simple coil, or of simple coils, i series of increasingdiameter ,thrpufghont the; A coil, or coils g'gofa series of sets 0simple tubes the b r tu esm each setdn re ng f om et o s t; and-a s of anumber; ftub ac aving a int rnal spir l of r s g pl h.

toward the outlet; of the tube,

Now according to this inventiQnthe evapo heated a ion i i fi ted an extnel be h vi g a :giral p s ageway a increasing area form therein bymeansof an internal aworm onspiral, the increasing area of the passagebeing obtained in any suitable way as by increasing the pitch of thescrew.

or the 'ameter of the tube or both, and in combina ion therewith thereemployed a pump adapted to forceinto andthrou h the heated;tube.definite quantities of the iquid per unit' of time and thus to insuresuch a rate of flow as may be necessary to obtain ther equired product,irrespective of varia-.

tions of resistance that-may occur in the tube during the process. ,Toenable the rate of flow to be controlled to suit varying condi tions ofthe liquid thus introducedprefen ably the pump: is rendered readilyadjnst,-'

the l;

able for example as hereinafter referred to,

Preferably the heated tube comprises a number of tubes connected inseries and with the'spiral passage way formed in the series oftubesincreasing in area from tube to tube. Thus each tube of the series maybe of greater diameter than the preceding tube in the series and theworms or spirals in each tube be of uniform pitch, or the tubes may beof uniform diameter and the pitch of the worms or spirals be greater insuccessive tubes, or by both the diameters of successive tubes. and thepitch of their contained worms or spirals increasing; The worm or spiralwithm the heated tube or each tube may extend nearly, but" not quite, tothe inner wall of the tube so that the liquid is partly compelled totravel through the tube in a spiral direction and partly caused to passover the edge of the worm or spiral so thatthe liquid completely coversthe inner surface of thetube instead of tending to travel along'in theangle between the tube and the back of the worm or spiral and.

leave the wall of the tube nearthe front of the. worm or spiral more orless uncovered, which uncovered surface reduces efiiciency andrendersprobable discoloration of the product by the -overheatin of partsof it. Theworni or spiral exten s tothe axis of b or: w rod e 7 c whichi fix d;

@ l y s ebw I y, order to exactlycontrol the quantity of: i elm-f rced,-throngh t e h ub i at t le pnmmpreferablrdriveethmugh 1 a lever. ,or thelikethat is moved by the-mo: A tor ,a certain definlte amount at eachstroke buy which is so. connected, to the, pump, that,

ec i s mra e ngi herma a i to say. it s on a t d t rem h a lostm t on dvi e wh ch is capable, of, eing accurately regu ated W thsase nde t y,Ehe exit from, ,the tube or tubes is .in a hamber in. whi h, 1 prefer byi y kc ntr t, al ae me ration takes p e be w en hest am a a. he toil dproduct This chamhen pr separation ei h r c mmu cate v on 3: anydesired. ortion 0t its st o e i fif'i' wi h w-o th a nd n r, the; lat erbeing employed; ii cases; whe e i is 1. 6%

amr d ce. a .far as po s b e thepress [sure on thezliq d be gg o ledtotthatithe wate ante; reamed m e m L t-s eam;

low-temperatufie Wh tth ach negis usedwithout'imcQm each strokepositively forces a certain quantity of the boiled product out, it maybe past a spring pressed or weighted valve as well as a ainst thepressure of the atmosphere. The p un er is or may be actuated by, steam,the supp y and exhaust of the steam being controlled by a mechanicallyoperated valve, preferably a rotary valve, which is driven from the samemotor that actuates the pum for forcing the liquid through the heatedtube.

Figures 1 and 2 show, in elevations at right angles to each other, anevaporating or concentrating machine embodying thls 'suitable guide rodm and which the rod h extends; inner end of such pin extends invention.Fig. v3 shows to a larger scale the upper portion of such machine insection. Fig. 4 is a horizontal section corresponding to the line A A ofFig. 3. Fi 5 and 6 show the heated tube, removed rom the machine, inside elevation and end elevation, respectively. Figs. '7 and 8 aredetail views. Fig. 9 is a central horizontal section of a controllingvalve. Figs. 10 and 11 are vertical sections res ectively correspondingto the lines B B, C of Fig. 9.

In the machine illustrated the pump a is of the reciprocating plungertype, is mounted on the machine standard I) and is driven from a watermotor 0 (it mighthowever be a steam motor, electric motor, a belt pulleyand belt from an independent driving shaft, or other convenient sourceof power) also mounted on the machine standard 6, through a crank diskd, crank pin e, link f, and a lever g the movement of which is constantand one end of which, in order to actuate the pump plunger/t, extendsbetween two nuts or screwed collars j mounted to work on right and lefthand screwed portions of the plunger 12. or a rod 72, connected thereto.The nuts j are prevented from rotating by the screwed rod I2. or plungeris provided with a hand wheel n whereby it can be rotated in order tomove the nuts or collars j toward and away from each other in order toregulate the amount of lost motion between the lever g and the pumpplunger 71. and so control the effective stroke of the pump. Normallythe screwed rod 12. or plunger is prevented from rotation by a springcatch, shown more clearly in ig. 7 and comprising aspring pressed pin 0adapted to work .in a bearing 2 through normally the into any one offour slots 9 formed in the upper art of the rod Il which at this part isho ow, as

the separating chamber by a plunger which at liquid partly shown.Inorder to turn the rod 71. the pin 0 must be first withdrawn by pullingit outwardly against the action of the spring 1'.

The pump draws liquid from a supply tank, not shown, supported it may beon a suitable part a of the machine standard base, and delivers itthrough a pipe (1 into the first of a nest of five tubes t which arelocated in a steam chest or chamber a mounted on the standard head 1).The tube ends, excepting the inlet and exit ends are connected together.in pairs by being brazed into junction boxes or headers w, also locatedin'the steam chest u and left free therein in order to allow freely forexpansion and contraction, and the arrangement is such that the liquidmust take a to and from course along the tubes in succession from theinlet to the outlet. The first three tubes 25 of the series are ofsmaller diameter than the fourth tube and the fourth tube is itself ofsmaller diameter than the fifth tube of the series and each tube isfitted with a worm or spiral Z having a rod 2 arranged centrally withinthe tube, such worm or spiral extending nearly, but not quite, to theinner wall of the tube. IVith'this construction, the tendency of theliquid and steam to move straight through the tube under theinfiuence ofthe difference of pressure is resisted by the worm or spiral whichcompels the greater portion of the liquid to have a movement in a spiralpath. In all cases whether the tube be horizontal, vertical or inclinedthe result-ant of the forces due to pressure difference, centrifugalaction, or gravity, on the li uid is more or less liable to drive italong in the angle be tween the spiral and tube and leave part of thewall of the tube uncovered. Now the space between the ed e of the wormor spiral and the tube, enabFes some of the liquid, which is compelledto travel through the tube mainly in a spiral direction, to pass the ede of the worm or spiral, and so maintain: e inner surface of the tubecompletely covered.

Under some circumstances, as when the tube is vertical and the movementis downward, gravity will also tend to cause the liquid to travel alongon the top face of the spiral, the steam rushing along underneath thespiral face, and it is inevitable that, under some conditions ofworking, the surface of the tube near the under side of the spiral willnot be properly covered with liquid and that some parts of the liquidwill be overheated and in some instances such as gelatin solutions,damaged. In all such cases, great advantage is found in limiting theaction of the splral by leaving a space between its edge and the tube sothat the travels in a spiral path with great advantage in efficiency ofheat transer and perfection of what is known as film tial-direction intoa cylindricalchamber 4 a with a tubular extension is connected to a sion8 is the ,lower closed end of a cylindrical plunger 13 which is" locatedcentrally within the separator 4 and which is guided, on a piston 14that is formed in one with or fixedto a fixed piston rod 15 .dependingfrom the top of the separator 4. The iston rod 15 is formed with twolongitudina passages 16 each connected to a pipe "17 that extendsthrough the steam chest 4 and is connected by an'external pipe'18 to avalve casing 19 hereinafter pistonrodpas'sags 16, Fig. 8, is in com-,munication throu h a lateral port or passage 20 with the cylindricalspace within the plunger 13 above the piston 14 and the other passage 16extends right through the piston 14 and is in communication with suchspace, below the piston. The stroke of the plunger 13is such that whenin its raised position, to which it is moved by steam admitted above thefixed piston 14, the boiled solution can flow into the tubular extension8 at evaporation, and partly travels more or lessaxially along the tube,thus keeping the. whole surface covered by leaking from that part of thespiral passage where a tendency to thicken up takes place to that partwhere the tendency is for the liquid to leave the surface of the tubebare or only thinly covered. Th clearance between the spiral and thetube is of less importance when the tube is horizontal and the diameteris relatively large in relation to the pitch, because gravity is not.then assisting in causing unequal spreading of liquid over the tubesurface and the effect of the steam pressure axially is reduced, sothat. a sufiiciently mobile liquid will spread more or less evenly overthe whole heating surface. The clear.- ance between the worm or spiraland the tube will vary somewhat according to the viscosity of theliquid.

It is evident that thick liq uids such as sugar solutions of say 90 Brixat 220 F. might be unevenly distributed and leave part of the tubesurface imperfectly covered, with a consequent -bad effect of heat onthe sugar, and in such a case the modified action of the spiral due tothe leakage space is of importance. a

The pitch of the worm or spiral 1 in'each of the tubes 15 is showngreater than that in the preceding tube but it may 'increase graduallyin some or all of the tubes so that, in the latter case, the spiralpassage way will be of gradually increasing area from the inlet of thefirst tube to the outlet of the last tube of the series. The dottedlines in Fig. 3 indicate a worm or spiral the pitch bf which increasesfrom the inlet end of the tube in which it is contained to the outletend thereof. The last heating tube t'of the series discharges in atangenis afterward forced down by'steam admitted below the piston, theboiled solution is there by forced out of the tubular extension past theweighted valve 9. .1

21 is a bracket bolted to the standard I) in position to support asuitable receiving pan 22 below the valve 9. Q

It will be understood that the piston rod passages 16 alternatelyconstitute steam and exhaust passages, and to control the sup ly of.steam thereto and therefrom the va ve casing 19 before mentioned isfitted with two other'pipes, one a main steam supply pipe 23, the otheran exhaust pipe 24 com and within the caslng 19 is arranged a rotaryvalve 25 which is constantly partly rotated to and fro by a lever arm 26on the valve spindle 27 and a link 28 such arm to the crank pin 6 of thepump motor driving disk at through an intermediate link The. branches 29of the casing 19 leading to the pi es 18 and the ipe 24 are on one levelan the branch 30 leading to the main steam pipe level, see Figs. 9, 10and is formed with an angle passage 31 at the level of the branches 29adapted to place either of the pipes 18 in communication with theexhaust pipe 24, and at the level of the branch 30 the valve is formedwith a Y- passage 32 adapted to place one or other of the pipes 18 incommunication with the steam pipe 23 through longitudinal grooves 33formed inthe periphery of the valve 25 and leading from the extremitiesof two of the arms of the Y passage 32 to the level of the branches 29of the ipes 18.

In one osition of t e valve, one of the piston r0 passages 16isconnected to the steam supply pipe 23 through one of the branches 29,the corresponding groove 33,

also located inthe steam chest to, a curved guide plate or web 5 withinthe chamber adjacent to the exit of the tube assisting in leading theoutflowing steam and boiled liquid against-the wall of the chamber 4 sothat a whirling or centrifugal action is thereby set up whichfacilitates the separation of the steam from the product as wellunderstood. The up er end of the separator chamber 4, hereina ter calleda separator,

condenser by a pip? 7 that extends through the steam chest a ove thenest of tubes 1 therein. I

The lower end of the separator 4 is formed 8 that extends; through andterminates just below the steam chest a whereits lower end is normallyclosed by a valve 9 carried on one end of a lever 10 ivoted at 11 tolugs on the steam chest an whose other end is so weighted at 12 as toconstantly press the valve 9 toward its seat.

Arranged to work in the tubular extenthe lower end of the separator and,when it described. One of the connecting 23 is at another 11. The valve25 valve passage 32, and the branch 30, and the ot 7 er to. thecondenser through the other branch 29, valve passage 31 and corresponding branch 29 in the other position of the valve the passage 16 that wasconnected to the steam supply is connected to the condenser and theother passage 16 is cut ofi from the condenser and connected to thesteam supply, in each case inv the manner described.

To prevent concentrated solution such as syrup from lying on the metalsurface of the piston rod 15 and thereby causing'or tending to causecrystallization-or graining of such solution, the upper end' of the.

plunger 13 .is fitted with an upwardly-extending tubular sleeve 40 thatsurrounds the piston rod, and the piston rod is formed with two smallholes 41 each communicating with one of the piston rod passages 16 sothat steam. under pressure is always passing through one or other of'thesmall holes 41 into the space between the piston rod 15 and the sleeve40.. y

The motor 0 is mounted on a bracket 42 bolted to the standard 6 and itsshaft 43 hasfixed on it a worm that gears into a worm wheel 44 fixed onthe shaft 45 of the driving disk 03.

The lower part of the steam chest or chamber u is fitted with a. drainpipe 46 furnished with a valve and which discharges into the hollowmachine standard'b; This standard is closed at top and bottom and nearits lower end has connected to it a discharge pipe 48. 47 is the steamsupply pipe to the chamber a.

What I claim is 1. In apparatusfor evaporating and concentrating liquidsan externally heated evapcrating tube'havlng fixed within it a spiralwhich extends nearly but not quite to the inner surface of the tube, andis adapted to form a spiral passage-way of increasing area, as set fortv 2. In apparatus for evaporating or consentrating liquids a tubularconduit having a spiral passage way withinit of increasing I itrea fromthe inlet to the outlet, means for 5) ieating said tubular conduitexternally, and a pump adapted to force into and through the passage Wayof said tubular conduit defin-itequantities of the liquid per unit oftime.

In apparatus for evaporating and concentrating liquids, a tubularconduit, means for heating said tubular conduit externally, a spirallocated within said conduit extendmg nearly but notquite tothe innersurface of said conduit and adapted to form a spiral passage way ofincreasing area from the inlet to the outlet adapted to' force into andthrough the passage way of said conduit definite quantities of liquidper unit of time.

4. In apparatus. for evaporating and con 'ternal'ly, and an 'of saidconduit definite tities of liquid per unit of the outlet of each the ofsaid conduit and means series and so to force into and through thecentrating liquids, a tubular conduit, means for heating said conduitexternally, a spiral located within said conduit extending nearly butnot quite to the inner surface of said conduit and adapted to form aspiral passage way of increasing area from the inlet to the outlet ofsaid conduit, and an adjustable pump adapted to force into and throughthe passage way of said conduit definite quantities of liquid per unitof time.

In apparatus for evaporating or concentrating iquids a tubular conduithaving a spiral passage way within of increasing area from the inlet tothe outlet of the conduit, means for heating said conduit exadjustable'pump adapted to force into and through the passage way quantities of theliquid per unit oftiinea In apparatus for evaporating and concentratingliquids, a tubular conduit, means for heating said conduit externally,spirals located within said tubular conduit, adapted to form a spiralpassage wa of increasing area from the inlet to the nu let, and meansadapted to force into and through the passage way of said tubularconduit definite quantities of liquid per unit of time.

In apparatus for eva crating and concentrating liquids, a num er oftubes connected in series, means for heating said tubes externally,spirals located within said tubes adapted to form a spiral 'assa'ge wayof increasing area from the in ct to the outlet, and means adapted toforce into and through the passage way of said tubes definite quantime.

In apparatus for evaporating and concentrating liquids, a series oftubes, junction boxes connecting the outlet of each tube except thelast-of the series to the inlet of the next tube, a spiral locatedwithin each tube of said series the pitch of thespiral of the first tubebeing smaller than that of the next tubeof the series and so on, meansfor heatingsaid. series of tubes externally, and means adapted to forceinto and through passage way. formed in said series of tubes by saidspirals definite quantities of liquid per unit of time.

, In ap aratus for evaporating and concentrating iquids, a series oftubes the tubes constituting the last of the series being of eaterdiameter than those constituting the ist of the series, junction boxesconnectin tube except the last 0 the series to the inlet of the nexttube, a spiral located within each tube of said series itch of thespiral of the first tube being smaller than that oi the next tube of theon, 'means for heatin said series of tubes externally, and means a aptedpassage way formed in said series of tubes by said s irals definitequantities of liquid per unit 0 time. 130

10. In apparatus for evaporating and concentrating llquids, a series oftubes, junction boxes connecting the outletof each tube except the lastof the series to the' inlet of the next tube, a spiral located withineach tube of said series extending nearly but not quite tothe innersurface of the tube the pitch of the spiral of the first tube beingsmaller than that of the next tube of the series and so on, means forheating said series of tubes externally, and means adapted to force intoand through the passage way formed in said series of tubes by saidspirals definite quantities of liquid per unit of time. a

11. In apparatus for evaporating and concentrating liquids, a series oftubes the tubes constituting the last of the series being of greaterdiameter than those constituting the first of the series, junction boxesconnecting the outlet of each tube except the last of the series to theinlet of the next tube, a spiral located within each tube of said seriesextending nearly but not quite to the inner surface of the tube thepitch of the spiral of the first tube being smaller than that of thenext tube of the series and so on, means for heating said series oftubes externally, and

meansadapted to force into and through the passage way formed in saidseries of tubes by said spirals definite quantities of liquid per unitof time.

12. In ap aratus for evaporating and concentrating liquids, a series oftubes the tubes constituting the last of the series being of greaterdiameter than those constitutingv the rst of the series, junction boxesconnecting the outlet of each tube except the last of the series to theinlet of the next tube, a spiral located within each tube of said seriesextending nearly but not quite to the inner surface of the tube thepitch of the spiral of the first tube being smaller than that of thenext tube of the series and so on, means for heating said series oftubes externally, and an adjustable pump adapted to force into andthrough the passage Way formed in said series of tubes by said spiralsdefinite quantities of liquid per unit of time.

Signed at London England this 17th day of December 1909. a

i EDWARD SHAW.

Witnesses:

H. D. JAMEsoN, CARL R. Loor.

